Blackmun’s “ongoing health issues resulting from prostate cancer” were cited as the reason for his immediate resignation, the USOC said in a statement. His departure also comes as the USOC faces public backlash and three congressional inquiries into the organization's handling of the Larry Nassar sexual abuse case and similar abuse allegations with other sports under the USOC umbrella.

“Given Scott’s current health situation, we have mutually agreed it is in the best interest of both Scott and the USOC that we identify new leadership so that we can immediately address the urgent initiatives ahead of us,” USOC chairman Larry Probst said in a statement.

“The USOC is at a critical point in its history. The important work that Scott started needs to continue and will require especially vigorous attention in light of Larry Nassar’s decades-long abuse of athletes affiliated with USA Gymnastics. We will be working with key stakeholders to help identify a permanent successor to Scott."

USOC board member Susanne Lyons will serve as interim CEO as a search begins for a permanent replacement. Blackmun had been the CEO since 2010.

PHOTOS: Stunning images from the Olympic closing ceremony

General view of fireworks as the Olympic flame is set off at the end of the closing ceremony of the Pyeongchang 2018 Winter Olympic Games at the Pyeongchang Stadium on February 25, 2018. FRANCOIS-XAVIER MARIT/AFP/Getty Images

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General view of fireworks as the Olympic flame is set off at the end of the closing ceremony of the Pyeongchang 2018 Winter Olympic Games at the Pyeongchang Stadium on February 25, 2018. FRANCOIS-XAVIER MARIT/AFP/Getty Images